[PATCH 20/44] Implement BCM2838 thermal sensor

[Sergey Kambalin]

Signed-off-by: Sergey Kambalin <sergey.kambalin@auriga.com>
---
 hw/arm/bcm2838_peripherals.c         | 12 ++++
 hw/arm/raspi4b.c                     |  1 -
 hw/misc/bcm2838_thermal.c            | 96 ++++++++++++++++++++++++++++
 hw/misc/meson.build                  |  3 +-
 include/hw/arm/bcm2838_peripherals.h |  2 +
 include/hw/misc/bcm2838_thermal.h    | 24 +++++++
 6 files changed, 136 insertions(+), 2 deletions(-)
 create mode 100644 hw/misc/bcm2838_thermal.c
 create mode 100644 include/hw/misc/bcm2838_thermal.h

diff --git a/hw/arm/bcm2838_peripherals.c b/hw/arm/bcm2838_peripherals.c
index df97953bbe..e7a9db97ab 100644
--- a/hw/arm/bcm2838_peripherals.c
+++ b/hw/arm/bcm2838_peripherals.c
@@ -37,6 +37,9 @@ static void bcm2838_peripherals_init(Object *obj)
     /* Random Number Generator */
     object_initialize_child(obj, "rng200", &s->rng200, TYPE_BCM2838_RNG200);
 
+    /* Thermal */
+    object_initialize_child(obj, "thermal", &s->thermal, TYPE_BCM2838_THERMAL);
+
     /* PCIe Host Bridge */
     object_initialize_child(obj, "pcie-host", &s->pcie_host,
                             TYPE_BCM2838_PCIE_HOST);
@@ -98,6 +101,14 @@ static void bcm2838_peripherals_realize(DeviceState *dev, 
Error **errp)
         qdev_get_gpio_in_named(DEVICE(&s_base->ic), BCM2835_IC_GPU_IRQ,
                                INTERRUPT_RNG));
 
+    /* THERMAL */
+    if (!sysbus_realize(SYS_BUS_DEVICE(&s->thermal), errp)) {
+        return;
+    }
+    memory_region_add_subregion(
+        &s->peri_low_mr, 0x15D2000,
+        sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->thermal), 0));
+
     /* Extended Mass Media Controller 2 */
     object_property_set_uint(OBJECT(&s->emmc2), "sd-spec-version", 3,
                              &error_abort);
@@ -197,6 +208,7 @@ static void bcm2838_peripherals_realize(DeviceState *dev, 
Error **errp)
                              BCM2838_MPHI_SIZE);
     memory_region_add_subregion(&s_base->peri_mr, BCM2838_MPHI_OFFSET,
                                 &s->mphi_mr_alias);
+
     /* PCIe Root Complex */
     if (!sysbus_realize(SYS_BUS_DEVICE(&s->pcie_host), errp)) {
         return;
diff --git a/hw/arm/raspi4b.c b/hw/arm/raspi4b.c
index 82b6b48d3c..c7fdf791d5 100644
--- a/hw/arm/raspi4b.c
+++ b/hw/arm/raspi4b.c
@@ -66,7 +66,6 @@ static void raspi4_modify_dtb(const struct arm_boot_info 
*info, void *fdt)
 
     /* Temporary disable following devices until they are implemented*/
     const char *to_be_removed_from_dt_as_wa[] = {
-        "brcm,bcm2711-thermal",
         "brcm,bcm2711-genet-v5",
     };
 
diff --git a/hw/misc/bcm2838_thermal.c b/hw/misc/bcm2838_thermal.c
new file mode 100644
index 0000000000..a488dc3da1
--- /dev/null
+++ b/hw/misc/bcm2838_thermal.c
@@ -0,0 +1,96 @@
+/*
+ * BCM2838 dummy thermal sensor
+ *
+ * Copyright (C) 2022 Maksim Kopusov <maksim.kopusov@auriga.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qapi/error.h"
+#include "hw/misc/bcm2838_thermal.h"
+#include "hw/registerfields.h"
+#include "migration/vmstate.h"
+#include "qemu/error-report.h"
+
+REG32(STAT, 0x200)
+FIELD(STAT, DATA, 0, 10)
+FIELD(STAT, VALID_1, 10, 1)
+FIELD(STAT, VALID_2, 16, 1)
+
+#define BCM2838_THERMAL_SIZE 0xf00
+
+#define THERMAL_OFFSET_C 410040
+#define THERMAL_COEFF  (-487.0f)
+#define MILLIDEGREE_COEFF 1000
+
+static uint16_t bcm2838_thermal_temp2adc(int temp_C)
+{
+    return (temp_C * MILLIDEGREE_COEFF - THERMAL_OFFSET_C) / THERMAL_COEFF;
+}
+
+static uint64_t bcm2838_thermal_read(void *opaque, hwaddr addr, unsigned size)
+{
+    uint32_t val = 0;
+
+    switch (addr) {
+    case A_STAT:
+        /* Temperature is always 25°C */
+         val = FIELD_DP32(val, STAT, DATA, bcm2838_thermal_temp2adc(25));
+         val = FIELD_DP32(val, STAT, VALID_1, 1);
+         val = FIELD_DP32(val, STAT, VALID_2, 1);
+
+         break;
+    default:
+         /* MemoryRegionOps are aligned, so this can not happen. */
+         warn_report("%s can't access addr: 0x%"PRIx64,
+                     TYPE_BCM2838_THERMAL, addr);
+         g_assert_not_reached();
+    }
+    return val;
+}
+
+static const MemoryRegionOps bcm2838_thermal_ops = {
+    .read = bcm2838_thermal_read,
+    .impl.max_access_size = 4,
+    .valid.min_access_size = 4,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void bcm2838_thermal_realize(DeviceState *dev, Error **errp)
+{
+    Bcm2838ThermalState *s = BCM2838_THERMAL(dev);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &bcm2838_thermal_ops,
+                          s, TYPE_BCM2838_THERMAL, BCM2838_THERMAL_SIZE);
+    sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
+}
+
+static const VMStateDescription bcm2838_thermal_vmstate = {
+    .name = TYPE_BCM2838_THERMAL,
+    .version_id = 1,
+    .minimum_version_id = 1,
+};
+
+static void bcm2838_thermal_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = bcm2838_thermal_realize;
+    dc->vmsd = &bcm2838_thermal_vmstate;
+}
+
+static const TypeInfo bcm2838_thermal_info = {
+    .name = TYPE_BCM2838_THERMAL,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(Bcm2838ThermalState),
+    .class_init = bcm2838_thermal_class_init,
+};
+
+static void bcm2838_thermal_register_types(void)
+{
+    type_register_static(&bcm2838_thermal_info);
+}
+
+type_init(bcm2838_thermal_register_types)
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index a6230ced43..dc67e6be3c 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -88,7 +88,8 @@ system_ss.add(when: 'CONFIG_RASPI', if_true: files(
   'bcm2835_thermal.c',
   'bcm2835_cprman.c',
   'bcm2835_powermgt.c',
-  'bcm2838_rng200.c'
+  'bcm2838_rng200.c',
+  'bcm2838_thermal.c'
 ))
 system_ss.add(when: 'CONFIG_SLAVIO', if_true: files('slavio_misc.c'))
 system_ss.add(when: 'CONFIG_ZYNQ', if_true: files('zynq_slcr.c'))
diff --git a/include/hw/arm/bcm2838_peripherals.h 
b/include/hw/arm/bcm2838_peripherals.h
index d52617f3bd..bb26aceb13 100644
--- a/include/hw/arm/bcm2838_peripherals.h
+++ b/include/hw/arm/bcm2838_peripherals.h
@@ -11,6 +11,7 @@
 
 #include "hw/arm/bcm2835_peripherals.h"
 #include "hw/misc/bcm2838_rng200.h"
+#include "hw/misc/bcm2838_thermal.h"
 #include "hw/arm/bcm2838_pcie.h"
 #include "hw/sd/sdhci.h"
 #include "hw/gpio/bcm2838_gpio.h"
@@ -69,6 +70,7 @@ struct BCM2838PeripheralState {
     MemoryRegion pcie_mmio_alias;
 
     BCM2838Rng200State rng200;
+    Bcm2838ThermalState thermal;
     SDHCIState emmc2;
     BCM2838PcieHostState pcie_host;
     BCM2838GpioState gpio;
diff --git a/include/hw/misc/bcm2838_thermal.h 
b/include/hw/misc/bcm2838_thermal.h
new file mode 100644
index 0000000000..bb6302a037
--- /dev/null
+++ b/include/hw/misc/bcm2838_thermal.h
@@ -0,0 +1,24 @@
+/*
+ * BCM2838 dummy thermal sensor
+ *
+ * Copyright (C) 2022 Maksim Kopusov <maksim.kopusov@auriga.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef BCM2838_THERMAL_H
+#define BCM2838_THERMAL_H
+
+#include "hw/sysbus.h"
+#include "qom/object.h"
+
+#define TYPE_BCM2838_THERMAL "bcm2838-thermal"
+OBJECT_DECLARE_SIMPLE_TYPE(Bcm2838ThermalState, BCM2838_THERMAL)
+
+struct Bcm2838ThermalState {
+    SysBusDevice busdev;
+    MemoryRegion iomem;
+};
+
+#endif /* BCM2838_THERMAL_H */
-- 
2.34.1